Building wall and partition structure



Dec. 8, 1964 File-:1 Oct 24,

J. J. DONLON BUILDING WALL AND PARTITION STRUCTURE 5 Sheets-Sheet lINVENTOR.

JOHN J. DON LON MJMZW ATTORNEY Dec. 8, 1964 J. J. DONLON BUILDING WALL.AND PARTITION STRUCTURE 3 Sheets-Sheet 2 Filed Oct. 24. 1960 INVENTOR.

JOHN J DONLON ATTORNEY Dec. 8, 1964 .1. J. DONLON BUILDING WALL ANDPARTITIO N STRUCTURE 3 Sheets-Sheet 3 Filed Oct. 24, 1960 INVENTOR.

JOHN

DONLON} ux 9% I ATTORNEY United States Patent 3,169,246 BUILDENG WALLAND IARTITHGN STRUCTURE .lohn J. Danton, 953 Hastings St, Baldwin, NX.Filed Get. 24, @619, Ser. No. 64,604 6 (Ilahns. (Cl. 189-64) Thisinvention relates to improved building structures, and particularlyrelates to building structures useful as walls, partitions, ceilings,and the like.

The invention has among its objects the provision of an improved panelstructure for use as a wall partition or the like, such panel structurebeing characterized by its economy, its attractiveness of appearance,and the ease with which it may be erected.

Another object of the invention resides in the provision of a novelbuilding structure composed of a plurality of aligned abutting panels,such structure including novel means for joining adjacent panels.

Yet another object of the invention, and particular embodiments thereof,resides in the provision of an improved wall or partition wherein atleast some of the vertical supports or mullions thereof are composed ofmembers forming integral parts of the panels of the wall or partition.

Still a further object of the invention lies in the provision of animproved panel for building structures, such panel incorporating novellyconnected internal bracing elements therefor.

Another object of the invention is the provision of an improved door anddoor-supporting structure for use with walls and partitions inaccordance with the invention.

The above and further objects and novel features of the invention willmore fully appear from the following description when the same is readin connection with the accompanying drawings. It' is to be expresslyunderstood, however, that the drawings are for the purpose ofillustration only, and are not intended as a definition of the limits ofthe invention.

In the drawings, wherein like reference characters refer to like partsthroughout the several views,

FIG. 1 is a fragmentary view in perspective of a first illustrativeembodiment of partition made in accordance with the invention;

FIG. 2 is a fragmentary view in perspective of a second embodiment ofpartition made in accordance with the invention;

FIG. 3 is a view in vertical cross section through the partition of FIG.1, the section being taken along the line 33 of FIG. 1;

FIG. 4 is a fragmentary view in vertical cross section through thepartition of FIG. 1, the view showing the structure of the door anddoor-supporting means associated with such partition, the section beingtaken along the line 44 of FIG. 1;

FIG. 5 is a view in horizontal section through the partition of FIG. 2,the section being taken along the line 5-5 of FIG. 2;

FIG. 6 is a fragmentary view in vertical section through the partitionof FIG. 2, the figure particularly showing a vertical support or mullionfor such partition, the sec- FIG. 10 is a fragmentary view inperspective of a corner of the door employed in the first disclosedembodiment of partition.

The building structure of the present invention is disclosed inconnection with two embodiments of inner partion which may be employed,for example, in an oifice building. It is to be understood, however,that the building structure in accordance with the invention is capableof much wider use, such structure lending itseld admirably to use inexterior walls of buildings, ceilings for rooms of buildings and forfalse walls to be applied to existing outer or inner wall structures.

In FIG. 1 the partition structure is generally designated 10. Partition10 is shown extending between a floor 11 and the ceiling 12 and as beingsecured thereto. The partition structure 10 is made up of a plurality ofsimilar aligned abutting panels 14 in its forward walls, such forwardwall including'a door 94 and a transom panel 99. The forward wall of thepartition is joined at vertical corner member 13 to an end partitionstructure 86, which may be of the same construction as the forward wallnow to be described.

The edge-abutting panels 14 are held between an elongated base member 15afiixed to the floor and an elongated upper member 16 secured to theceiling. The lefthand and right-hand end panels shown in FIG. 1 areadditionally secured to the left-hand and right-hand vertical cornersupport members 17 and 18, respectively. The structure of members 17 and18, and their manner of interaction with the panels will be described inconnection with the description of similarmembers 17 and 18' shown inFIGS. 2 and 5. A

The construction of the lower supporting member 15 for the panels isparticularly illustrated in FIG. 3. As there shown, element 15 has abox-like section, having a horizontal bottom wall 19 which is supportedhorizontally somewhat above the level of the floor by depending parallelflanges 20 and 21. The bottom wall 19 is centrally thickened at 22, andhas longitudinally spaced passages therethrough to receive the upperends of vertical members 24 secured to the floor. Members 24 may be inthe nature of bolts having their lower ends imbedded in the floor.Members 24 have upper threaded shanks 25 protruding through the openingsin element 22, a nut 26 on shank 25 securely attaching member 15 to thefloor. Member 15 has a vertically extending rear wall 27 and ahorizontally extending upper wall 2 overlying bottom wall 19. There isthus formed a raceway 36 within member 15, such raceway affording spacefor electrical outlet boxes such as that shown at 31, whererequired, andfor electrical conduits connecting the outlet boxes.

Above the upper element 29 base member 15 is provided with alongitudinally extending vertical flange 32 which forms, in efiect, anextension of wall 27. An elongated cap member 34 is provided to coverraceway 39, cap member 34 conveniently providing openings therethroughfor access to the electrical receptacles in the raceway. The plate 34has its lower edge removably received within a longitudinally extendingvertical recess 35 in the outer edge of member 19, an upper extension offlange 21 forming the outer wall of such recess, as shown. Meansgenerally designated 35 is provided to form a snap connection betweenthe upper portion of plate 34 and the outer edge of element 29. Means 36is formed by an inwardly and downwardly turned bead 37 on the inner faceof plate 34, head 37 resiliently and releasably cooperating with anoutwardly and upwardly turned bead 39 on the outer edge of member 29.Above member 29 the plate 34 extends into a flange portion 4% which isparallel to and spaced from flange 32, member 29 and flanges 32 and 40forming a seat or pocket for the reception of the edge of a panel 14.

T he upper elongated panel securing member 16 is likewise shown indetail in FIG. 3. Element 16 is generally in the form of a hollowopen-bottomedchannel member and has an upper wall 42 which may besecured to the ceiling 12 as by screws 43. Depending from upper wall 42is av vertical flange 44 which confronts and is aligned with the flange32 of bottom panel securing member 15. Member 16 is provided with aremovable cover strip 45 which is secured to the body of the member 16by snap attaching means generally designated 46. An inner verticallydepending flange or web 47 is attached to member 42 as shown, at thebottom flange 47 being directed outwardly and thence downwardly into ashallow horizon be securely attached to the body of member 16, the inner7 surfaces of flanges 49 and 51 may be serrated or provided withsuitable recesses into which the ends of hook-like members 50 and 52will snap.

The structure of the panels 14 in the embodiment of FIG. 1 is shown inFIG. 3. Each panel has a bordering frame made up of frame portions 54which extend along the top, bottom, and vertical edges of the panel.Such frame portions are joined at the corners of the panel as by beingmitercd and welded or otherwise secured together along joints 65, asshown in FIG. 9. Each such frame member has a main web'portion 55 whichhas a width substantially equaling the panel thickness. Web 55 has asmooth inner surface facing inwardly toward the main extent of thepanel. One outer edge of each frame member, shown at the right in FIG.3, is provided with a relatively thick flange 56; from the laterallyinner edge portion of part 56 there extends outwardly a further, thinnerflange 59, thereby forming a shoulder 57 lying closer to the web 55. Theother edge of each frame member 54, shown at the left in FIG. 3, bearstwo similar longitudinally and outwardly extending flanges 60 and 61,such flanges being parallel and presenting a groove 62 therebetween.Flanges 6t and 61 have their outer free edges disposed at the same levelas shoulder 57. Preferably the outer surface of web 55 is provided withtwo longitudinally extending screw-receiving channels 64, as shown,whereby the frame members may be additionally secured together or havebraces or other similar parts secured thereto by self-tapping screws.

When the panels 14 are of substantial vertical and horizontal extents,it is preferred that they be provided with additional inner bracingmembers. In the embodiment of partition shown in' FIG. 1, the upperportionsof the coverings layers of each of panels 14 are clear ortransparent, and the lower portions of the covering members for suchpanels are of either a solid color or are made opaque as by beingfrosted. Consequently, in the first illustrative embodiment the bracingmembers for the panels are confined to the lower portions of the panels.Thus as shown in FIG. 3 there is provided an inner cross brace 66 whichis located horizontally within the panels at the junction between theclear and opaque portions thereof. Brace member 66 has a main webportion 67 which is of the same length as web 55 of frame members 54.The opposite edges of. brace member 66 are provided with flanges 69connected at their vertical centers to the edges of web 67. The upperand lower edges of vertical flanges 69 are provided with shorthorizontally and inwardly projecting flanges 76. may be attached to thevertical'frame members of the panel as by being welded thereto, by oneor more selftapping screws received in a screw race such as that shownat 71' in FIGS. 3 and 8, or both. Where it is de- .70 Brace member 66sired that there be a clear shadow line through the trans parentportions of the panels, there may be additionally provided a thin stripor plate 74 which lies upon and is secured to the upper flanges 70 ofhorizontal brace member 66.

The panels 14 are provided with thin covering skins or layers 71 and 72which overlie and are secured to the respective outer and inner flangeson frame members 54 and the flanges on the inner. brace member ormembers. Cover members '71 and 72 may be made of plastic, metal, wood,or any other suitable material. In the embodiments shown, members 71 and72 are made of plastic sheets and are adhesively secured to the innerand outer flanges of the frame members and brace. A pair of mating framemembers 54 of the embodiment of FIG. 2 are shown in FIG. 5 where suchcombination forms a. vertical support designated 82. As above explained,members 14' are similar to members 14 of the first embodiment, andinterfit in the same manner. As shown in FIG. 5, the width of thebordering portions of the respective mating frame members to which thethin covering layers or skins 71 and 72" overlie and to which they areadhered are substantially the same on both the (male) flange '56 and onthe mating (female) portion carrying flanges 60 and 61. In other words,the width of flange 60 substantially equals the width of thatportion offlange 56' extending from the smooth inner edge of the frame member 54'to the root of thefurther, thinner flange 59. As a result, not only arethe lines of abutment between adjacent panels substantially inalignment, lying substantially in a central transverse plane through themating frame members 54' forming the combination 82, but the width ofthe surfaces to which the covering skins or layers 71 and 72 are adheredis uniform completely around the panels on both sides thereof. When thecovering members 71 and 72 are made of metal sheets, they may be securedto the frame members and brace by being welded thereto. Cover members 71and 72 are of such vertical extent that their upper and lower edges lieflush with the upper and lower edges of flanges 60 and 61, as shown atthe left in FIG. 3, and lie flush with the shoulders 57, as shown at theright in FIG. 3.

The cover members 71 and 72 are of such width that their vertical edgeslie flush with the outer free edges of the flanges 60 and lie flush withthe shoulder 57 of the vertical frame members. Such relationship isillustrated in FIG. 5 in connection with the embodiment of partitionshown in FIG. 2. As a result'of such construction, the panel coveringmembers designated 71 and 72 in connection with the embodiment of FIGS.1 and 3 and '71" and 72" in connection with the embodiment of FIGS. 2and 5 closely abut along vertical lines so that the joints betweenpanels are not readily visible. The outer line of vertical juncturebetween contiguous panels 14 is shown at 75 in FIG. 1. An inner junctionline between contiguous panels in the embodiment of FIGS. 2 and 5 isshown at 76 in FIG. 5.

In some instances it may be desirable to supplement the singlehorizontal internal brace 66 shown employed in the panels 14. Thus inthe generally similar panels 14' of the embodiment of FIGS. 2 and 5there are employed a plurality of vertical and horizontal internalbracing members. Such bracing members may have a section similar to thatof member 66, and may advantageously be joined in the manner shown inFIG. 8. As shown in FIG. 2, three vertically spaced horizontal bracingmembers 66 are employed, there being a number of short vertical bracingmembers 66" interposed between the horizontal mem- A typibers 66' and/orthe horizontal frame members. cal joint 77 between vertical andhorizontal internal bracing members 66' and66", respectively, is shownin FIG. 8. As there shown, the web 67 has its lower end lying in atransverse plane lying below the lower ends of the side vertical flanges69 and of the inwardly projecting flanges 70, which also lie in atransverse plane. The

web 67 of vertical member 66' is inwardly slotted at its lower ends toform grooves 79 and tongues 80. The slots are so located and of suchconfiguration that the flanges 70 of member 66" are snugly receivedtherein, tongues 80 are accurately received beneath flanges 70 of member66", and shoulders 81 at the lower ends of flanges 69 and 70 of member66 snugly engage the upper surfaces the latter in canted position,following which members 66, thus prepared, may be readily connected totwo horizontal brace members 66 by being introduced between the latterin canted position following which members 66" may be turned to lietransversely of members 66', as shown.

In the embodiment of partition shown in FIGS. 2 and 5, the panels 14'extend only part way from the floor to the ceiling; the partition formedby a plurality of aligned abutting panels 14 is supported by verticalcorner members 17 and 18', and, when required, by one or more verticalmembers 82 which in this instance are formed by interfitting abuttingframe members of contiguous panels as shown in FIG. 5. As there shown,the vertical frame members 54 of panel members 14 are the same insection as the side frame members 54 of the above described panels 14.When consecutive panels are mounted in mating engagement, as shown inFIG. 5, the tongue 59' of one such frame member is received within thegroove 62' of the other. The inner and outer covering members 71 and 72'meet along vertical lines '75 and 76', respectively.

The upper edges of panels 14' are provided with a cap member 84 which isin the form of a downwardly open channel. Cap member 84 has an openingtherethrough at the location of vertical support 82. The upper end ofmember 82 may be secured to the ceiling 12 through the medium of abracket 85, as shown in FIG. 6.

The corner member 18 of the first embodiment of partition and the cornermember 18 of the second embodiment thereof may be constructed in themanner shown in FIG. 5 in connection with member 18' As there shown,such member is of generally box-like configuration, having a front wall87 and a side wall 90. The left-hand end and upper faces of member 18 asit is shown in FIG. 5 are open to receive the end of the main partitianand of a side partition 86, respectively. Inwardly projecting verticalflanges 89 and 91, respectively, form closed joints between member 18'and the main and side partitions. In order to close the joint betweenthe inner surfaces of the main and side partitions, member 18 isprovided with a vertically disposed inner web member 92 extendinginwardly from side 90 of member 18' and thence being angularly directedso as to pass between the confronting inner edges of the two partitions.Web 92 carries a vertically extending filler member 94 on its outeredge, such filler member masking the inner joint between the partitions.

The embodiment of partition shown in FIGS. 1 and 3 incororporates a door94. To support such door there is provided a vertical door jamb 95 whichis connected to the main partition in the manner particularly shown inFIG. 7. Jamb 95 is of box-like configuration, having an open edgereceiving the vertical edge of the panel 14 adjacent the door opening.Member 95 has a generally fiat web member 96 from which there protrudesinwardly of the door opening a narrow vertical flange 97. Web 96 andflange 97 may be employed to form a seat for either the hinged or thefree edge of the door 94, depending upon the manner of mounting of thedoor. A vertically short transom panel 99 is provided in the partitionabove the door opening, the lower edge of panel 99 being bordered by ahorizontal member having a construction similar to jamb 95. The thirdedge of the door opening is bordered by a similar vertical member 101.

The construction of the door is shown in detail in FIGS. 4 and 10. Asthere shown, the door has a frame made up of two vertical frame members,one of which is shown at 101, a top frame member mama a bottom channelconfiguration, as shown more particularly in FIG 10, and are providedwith longitudinally extending screw races on their inner surfaces tofacilitate their assembly. A vertical frame member 101, on the hingedside of the door, is in the form of a channel member having a main web113 and spaced parallel flanges 112 projecting along the outer edge ofsuch web. Frame member 101 thus presents a longitudinally extendingrecess 106 which is employed in this instance for the reception of thebutts of door-mounting hinges, not shown. Recess 106 may be providedwith a cover plate 167 which is received within longitudinally extendingconfronting grooves 114 on the outer ends of flanges 112.

The bottom frame member 104 of the door is shown more particularly inFIG. 10. As there shown, frame member 104 has spaced parallellongitudinally extending inner and outer webs 109 which are connected atgenerally their mid portions by a horizontally extending inner web 110.Frame member 104 is completed by an inner, horizontally extending web111 which is connected to the inner edges of side webs 109. Thevertically and horizontally extending frame members of the door aresuitably connected as by being interfitted and joined as shown at 115 inFIG. 10. The frame members may be connected as by being welded together,by self-tapping screws extending through the one member and threadedlyengaged with the screw races of the other, or both.

The inner edges of the vertical and horizontal frame members of the doorhave two spaced parallel inwardly projecting flanges 116 extendingtherealong. Flanges 116 on the respective door frame members are spacedinwardly from the edges thereof to form recesses or seats 117 on theinner and outer edges of the door. Inner and outer covering panels orskins 119 and 1219, respectively, are disposed in the respective seatson the door frame. Panels 119 and 129, which may be made of any suitablematerial such as clear or opaque plastic, metal sheets, or wood, may besecured in the recesses in the door frame in any suitable manner, suchas being adhered thereto by a suitable cement.

The wall and partition structure of the present invention isparticularly characterized by its attractive appearance, its economy,and the ease with which it may be asembled and disassembled. The variousstructural parts of the wall and partition member of the invention,

such as the frames of the panels, the floor and ceilingmounted channelmembers for the partition, the door frame members, etc., may be formedof suitable materials such as metal, plastic, or the like. It ispreferred, for reasons of strength, that such parts be formed of metal;because of the uniformity of the sections of the panel frame parts, thebraces therefor, the floor and ceilingmounted channels, and so forth,such parts are advantageously formed by being extruded through suitablyshaped dies.

Although only a limited number of embodiments of the invention have beenillustrated in the accompanying drawings and described in the foregoingspecification, it is to be especially understood that various changes,such as in the relative dimensions of the parts, materials used, and thelike, as well as the suggested manner of use of the apparatus of theinvention, may be made therein without departing from the spirit andscope of the invention as will now be apparent to those skilled in theart. Thus the wall and partition structure of the invention lends itselfadmirably, for example, to the use of thermal and sound insulationwithin it. When panels or portions of panels are opaque, as are thelower portions of the panels 14 in FIGS. 1 and 3, the space between theouter covering members 71 and 72 may be filled with insulating materialsuch as styrene foam. The space between the covering elements on thedoor may likewise be filled with insulating material if desired.

What is claimed is:

1. A wall structure comprising a plurality of aligned interlocked panelsdisposed in edge engagement, each panel having a border frame includingelongated channel shaped frame members disposed in opposed alignedrelationship along abutting edges of the panels at the jointstherebetween, the channel shaped frame members being open toward therespective outer edges of the panel, said frame members each forminggenerally one-half of a hollow rectangular beam and having a broad baseextending normal to the broad extent of its respective panel and spacedparallel side flanges at the opposite side edges of the base andextending at right angles to the base,

the said side flanges on the elongated frame members of contiguouspanels having formations thereon which lie completely between the broadopposite surfaces of the panels, which extend longitudinally of theabutting panel edges, and which mutually interfit, the interfittingformations of contiguous panels being reversed mirror images of eachother, the interfitting formations on the side flanges of each of thesaid interfitting frame members comprising a longitudinally extendingtongue on one of said side flanges and a longitudinally extending groovein the other of said side flanges, the width of the groove beingsubstantially equal to the thickness of the tongue, the tongue of oneframe member at a joint between contiguous panels being snuglyreceivable within the groove on the other frame member upon relativemovement of aligned panels thus to be joined toward each other in theircommon plane, there being longitudinally extending transverse endsurfaces of substantial lateral extent on the side flanges of contiguouspanels disposed, respectively, on the outer side of the tongue, on thesaid one side flange andon the outer side of the groove of the otherside flange, said transverse end surfaces of the side flanges ofcontiguous panels lying laterally outwardly of the tongues and groovesof the interfitting frame members on both sides of the wall structureabutting each other when the panels are in joined operative position,said frame members having edge portions of appreciable width extendingtherealong on both sides of the panels and lying parallel to the broadextent of the panels, said edge portionsmeeting the transverse surfaceson the frame members at the ends of the panels at solid right angles,each panel having a separate covering layer of material lying on eachside of the frame and having its edge portions overlying and aflixed tothe said edge portions on the respective'sides of the frame member, thecovering layers on each of the panels extending to the outer edges ofthe frame members of the respective'panels, whereby the respectivecovering layers of contiguous panels abut each other along a line oneach side'of the panels in the wall structure.

2. A wall structure as claimed in claim 1, wherein the tongue of each ofthe interfitting frame members'extends along the inner edge of the oneflange of such frame rnember, and wherein the groove in said otherflange of each of the interfitting frame members is located generallylaterally centrally within said other flange.

3. A Wall structure as claimed in claim 1, wherein the iransverse endsurfaces of the side flanges of the interitting frame members ofcontiguous panels which lie lat- :rally outwardly of the tongues andgrooves of such panels lie in the same plane transverse to the broad ex-;ents of said panels, said edge portions of the frame memaers on bothsides of the panels are of substantially the same width, and wherein thecovering layers on both sides of each panel are atlixed to said edgeportions by being adhered thereto.

4. A wall structureas claimed in claim 1, wherein the panels arerectangular, the frame members border all four sides of the panels, allof the border frame members of the panels are similar wherein the framemembers of each panel. are all similarly disposed, and wherein the framemembers of a given panel are disposed oppositely from the frame membersofanother panel which is matingly interlocked with an edge of said givenpanel.

5. A generally channel-shaped structural member generally in the form ofone-half of a hollow rectangular beam adapted for use as the border of apanel, said member comprising a base of substantial width having a firstflange extending along one side edge thereof, a second flange extendingalong the other side edge of the base, and a third flange spacedlaterally inwardly of, close to,

and extending parallel to the second flange so as to present an opengroove between the second andthird flanges, all of said flanges beingpositioned on the same side of the base, a fourth flange, thinner thanthe first flange and having a thickness substantially the same as thewidth of the groove, extending from the laterally inner edge of thefirst flange and parallel thereto, there being a shoulder on thelaterally outer edge of the first flange at the root of the fourthflange, the shoulder and the outer edge of the second flange remote fromthe base lying in the same plane parallel to the web, said structuralmember being adapted to mate with an identical member .in reversedposition to form a hollow rectangular beam with the fourth flanges ofeach of the mating members snugly received within the groove between thesecond and third flanges of the respective opposite member and withshoulder on the first flange in engagement with the outer edge of thesecond flange, the members when thus mated being retained in accuratealignment by said engagement therebetween.

6. A structural member as claimed in claim 5, wherein the fourth flangehas a height measured from said shoulder which approximates but does notexceed the depth of the groove measured from the said outer edge of thesecond flange.

References Cited by the Examiner UNITED STATES PATENTS 1,420,473 6/22Dawson et a1. 189-34 1,772,286 8/30 MacDonald 189-34 1,883,871 10/32Bohnsack 189-34 2,237,098 4/41 Gieseking 189-34 2,612,243 9/52 Campbell189-34 2,664,182 12/53 Williams et al. 189-46 2,744,590 5/56 Butts189-36 2,765,056 10/56 Tyree 189-46 2,976,969 3/61 Gillespie 189-342,981,383 4/61 Dunn 189-36 3,001,613 9/61 McBerty 189-34 3,018,859 1/62Struben 189-34 FOREIGN PATENTS 856,010 3/40 France.

RICHARD W; COOKE, 1a., Primary Examiner.

JOEL REZNEK, CORNELIUS D. ANGEL, JACOB L.

NACKENOFF, Examiners.

1. A WALL STRUCTURE COMPRISING A PLURALITY OF ALIGNED INTERLOCKED PANELSDISPOSED IN EDGEGEMENT, EACH PANEL HAVING A BORDER FRAME INCLUDINGELONGATED CHANNEL SHAPED FRAME MEMBERS DISPOSED IN OPPOSED ALIGNEDRELATIONSHIP ALONG ABUTTING EDGES OF THE PANELS AT THE JOINTSTHEREBETWEEN, THE CHANNEL SHAPED FRAME MEMBERS BEING OPEN TOWARD THERESPECTIVE OUTER EDGES OF THE PANEL, SAID FRAME MEMBERS EACH FORMINGGENERALLY ONE-HALF OF A HOLLOW RECTANGULAR BEAM AND HAVING A BROAD BASEEXTENDING NORMAL TO THE BROAD EXTENT OF ITS RESPECTIVE PANEL AND SPACEDPARALLEL SIDE FLANGES AT THE OPPOSITE SIDE EDGES OF THE BASE ANDEXTENDING AT RIGHT ANGLES TO THE BASE, THE SAID SIDE FLANGES ON THEELONGATED FRAME MEMBERS OF CONTIGUOUS PANELS HAVING FORMATIONS THEREONWHICH LIE COMPLETELY BETWEEN THE BROAD OPPOSITE SURFACES OF THE PANELS,WHICH EXTEND LONGITUDINALLY OF THE ABUTTING PANEL EDGES, AND WHICHMUTUALLY INTERFIT, THE INTERFITTING FORMATIONS OF CONTIGUOUS PANELSBEING REVERSED MIRROR IMAGES OF EACH OTHER, THE INTERFITTING FORMATIONSON THE SIDE FLANGES OF EACH OF THE SAID INTERFITTING FRAME MEMBERSCOMPRISING A LONGITUDINALLY EXTENDING TONGUE ON ONE OF SAID SIDE FLANGESAND A LONGITUDINALLY EXTENDING GROOVE IN THE OTHER OF SAID SIDE FLANGES,THE WIDTH OF THE GROOVE BEING SUBSTANTIALLY EQUAL TO THE THICKNESS OFTHE TONGUE, THE TONGUE OF ONE FRAME MEMBER AT A JOINT BETWEEN CONTIGUOUSPANELS BEING SNUGLY RECEIVABLE WITHIN THE GROOVE ON THE OTHER FRAMEMEMBER UPON RELATIVE MOVEMENT OF